1. Field of the Invention
This invention relates generally to reflectors and in more particular to an improved reflective sign for uses such as roadside traffic signs.
2. Background of the Invention
With the dawn of the automobile came the need for traffic control devices. Originally, each traffic sign was cut to a unique shape for identification. Since electricity was not wide spread, painted signs were used for traffic control. With the increase of automobile use around the clock, the traffic signs began to be painted with as reflective a paint available for viewing at nighttime. Initially, the reflective paint was used on wooden signs and then on more durable signs constructed of metal, including laminated signs. Presently, roadway signs have been constructed using tiny glass beads added to the paint to increase overall reflectivity.
Examples of the use of glass beads include U.S. Pat. No. 2,379,741 issued to McKenzie; U.S. Pat. No. 3,065,659 issued to Palmquist; U.S. Pat. No. 3,494,912 issued to Mitsuo Toyama et al.; U.S. Pat. No. 3,877,786 issued to Booras et al.; U.S. Pat. No. 3,922,433 issued to Patterson et al.; U.S. Pat. No. 3,934,065 issued to Tung; U.S. Pat. No. 3,994,086 issued to Mizuochi; U.S. Pat. No. 4,025,674 issued to Mizuochi; U.S. Pat. No. 4,082,426 issued to Brown; U.S. Pat. No. 4,099,838 issued to Cook et al.; U.S. Pat. No. 4,519,154 issued to Molari, Jr.; U.S. Pat. No. 4,544,586 issued to Molari, Jr.; U.S. Pat. No. 4,555,161 issued to Rowland; and U.S. Pat. No. 4,995,185 issued to Cheng.
The current state of the art is to put the beads on a paper or web backing and cover with a thin laminate. The other side of the paper or web is coated with a special adhesive so it will stick to the aluminum. A further enhancement is to use a heat activated adhesive to improve the bonding. In this process, the aluminum is heated and the paper or webbing sticks to it. Signs out in the field use stickers put on metal backing, and are painted with a message, design, symbol, etc. or combinations thereof, i.e. STOP, WRONG WAY. Once the sticker is on, the sign is ready for stencil and paint. However, when painting the sign, a minimal amount of paint is utilized to avoid covering up the reflective media. Presently, the colorant or paint is included on the inside of the laminate. However, during the heating process the paint on the inside the sticker becomes damaged. Additional damage occurs during the installation in the field. When the sign is fastened to a sign post, the bolt cuts small slits into the laminate. Thus, moisture is allowed to get into the sign, and with normal daily temperature swings, the signs begins to de-laminate and within weeks, the sign is ruined.
Other examples of reflective roadway signs and markers include the following:
(1) U.S. Pat. Nos. 5,050,327 issued to Woltman discloses a sign having a face bearing an informational legend thereon. The face is made up of one or more legend portions and one or more background portions. The legend and background portions define cross-sectional segments of the sign. At least part of at least one of the legend segment or background segment is both retro-reflective and translucent. Typically, the legend and background portions of the face are of contrasting colors to enhance the legibility of the information displayed on the sign. The backing member of the sign must be translucent or transparent in at least any segment of the backing member which is part of the translucent segment of the sign. This sign is better seen at night than conventional signs only when the sign is backlit.
(2) U.S. Pat. No. 3,409,344 issued to Balint et al. discloses a roadway reflector comprising a hollow housing which has inclined side and end walls and a flat top wall. The housing is molded in situ about the periphery of previously molded reflective inserts so that the inserts are in the end walls. The inserts have substantially flat outer surfaces and a plurality of retro-reflective prisms on the inner surfaces thereof, the axes of the prisms forming an angle with the plane of the insert and in turn with the pavement when the marker/reflector is in position such that the light beams from the automotive vehicle are reflected back to the eyes of the driver.
Though nearly a century has passed since the use of automobiles as way of transportation began, adequate traffic signs, especially for easy viewing at night, are still missing in the art. Thus, what is needed in the art is a sign having increased reflective means for greater viewing at nighttime as compared to present conventional signs. In addition, the sign needs to be more durable and able to last longer than signs presently in use. It is therefore, to the effective resolution of the aforementioned problems and shortcomings that the present invention is directed.